In short the problem is that WordPress automatically converts quotes in your post to “smart” quotes.
Normally this wouldn’t be a problem for you. But it will for someone who wants to copy and paste the content from your blog to their site.
You can use Alex’s WP Unformatted plugin to disable Smart Quotes on a post wise basis.
I guess a good thing to do would be to put code in a seperate text file and provide a link to it.
As for smart quotes, I guess it is wait and watch as of now.